This invention relates to a device for manually opening flexible packages, to be precise, flexible packages formed by bags made from plastics film which are closed by a weld line which is arranged at the filling mouth thereof in such a way as to leave a free skirt of the bag for the formation of holding and/or suspension means therefor, and more particularly the bags of this type which are for containing a plurality of articles which must be kept a controlled-moisture environment and/or be removed one by one, in one or more operations, through a delivery orifice of small section, which must be small so as to maintain the internal environment as long as possible and avoid the uncontrolled spilling of the bag content.
The majority of flexible packages of the plastics film bag type, where the mouth is closed by a weld line, lack specific manual opening means and must be opened either with the use of scissors, knives or other means, by which it is possible attain control of the position and section of the aperture, or by tearing with brute force, whereby neither the position nor the size of the aperture can be controlled.
Where the packaged article is one in number, the means used for opening the package are of no import, since it must be disposed of. On the other hand, where the articles enclosed are plural in number, and they are to be used one by one or in small numbers in each removal operation, some integrity of the package must be maintained so as adequately to contain the remaining articles for keeping them for future use. In this case, it is of interest to form an aperture in the pack, serving as a delivery orifice for removal of the articles, which is of the smallest possible size, depending on the dimensions of the articles. In such cases, it is absolutely necessary to use scissors, knives or other cutting instruments, so as to form the aperture at a particular point and with the resulting size of the delivery orifice being adjusted to the dimensions of the articles.
Under these circumstances, the problem may arise that the user does not have to hand the appropriate tools for forming the aperture in the desired way, or the operation is troublesome, such as is the case where the user is up a stepladder or in another situation where handling of the package is difficult.
Thus, for all cases, it would be desirable to have an arrangement allowing the controlled opening of flexible packages, by direct manual operation, without the need for any tool whatsoever.
With a view to satisfying such need, the device for opening flexible packages according to the invention has been developed. This consists of the arrangement, at one side end of the filling mouth of the bag, of a weakening line of defined length and of stiffened edges which, being located between the weld line of closure of the bag mouth and the free edge of this mouth, is directed in such a way as to be located in a contemplated trajectory of manual tearing of the bag, which intersects the said weld line of closure and extends across the corner of the bag immediately adjacent the weakening line.
One feature of the invention is to be found in the fact that the weakening line arranged in the bag filling mouth is formed by a line of cut which passes through the walls of said mouth and is stiffened by a perimetral weld line, forming a buttonhole-like arrangement. Alternatively, the weakening line contemplated in the bag filling mouth may be formed by a perforated line, the perforations of which extend through the walls of the mouth and which may in turn by stiffened by a perimetral weld line.
A further feature of the invention resides in the fact that the weakening line is located between two parallel weld lines, one of which is the weld line of closure of the bag and the other is disposed in the skirt of the mouth, comprising between both holding and/or hanging means for the bag.
Yet a further feature of the invention is to be found in the fact that the extension of the weakening line intersects the weld line of closure at an angle of about 60xc2x0.
The invention envisages that the ends of the weakening line are respectively equidistant from both weld lines and the distance between the end closest to the weld line of closure and the side edge of the bag is determined by the dimension that the delivery orifice is required to have to allow for removal of the packaged articles one by one.
It is also envisaged that the section of the delivery orifice resulting from a tearing operation is of such a small size that, when open, it allows the controlled environment inside the bag to be essentially maintained and controlled delivery of the packaged articles.